Measurement of combined glenoid and Hill–Sachs lesions in anterior shoulder instability. Issue 3 (July 2017)

• Record Type: Journal Article
• Authors: Rouleau, Dominique M.; Garant-Saine, Laurianne; Canet, Fanny; Sandman, Emilie; Ménard, Jérémie; Clément, Julien
• Is Part Of: Shoulder & elbow. Volume 9:Issue 3(2017)
• Page Start: 160
• Page End: 168
• Publication Date: 2017-07
• Subjects: bone loss -- glenohumeral joint -- measurement evaluation -- preoperative quantification -- shoulder instability -- simple method; Elbow -- Diseases -- Periodicals; Elbow -- Surgery -- Periodicals; Shoulder -- Diseases -- Periodicals; Shoulder -- Surgery -- Periodicals; Shoulder -- Periodicals; Elbow -- Periodicals; Shoulder Joint -- Periodicals; Elbow Joint -- Periodicals; 617.572005
• DOI: 10.1177/1758573216681208
• Languages: English
• ISSNs: 1758-5732

Abstract

Background: Recurrent glenohumeral anterior instability (RGAI) frequently induces combined glenoid and Hill–Sachs bone lesions and is a risk factor for soft tissue repair failure. This cohort study describes a simple preoperative quantification method for bone loss, the Clock method, the first that combines glenoid and humeral lesions. Methods: Computed tomography scans of 34 shoulders with RGAI were twice reviewed by three independent observers, who measured bone lesions using the new Clock method and existing validated methods. Intra- and inter-observer reliability of the Clock method was evaluated (intraclass correlation coefficient). Pearson correlation was used to correlate Clock method with existing methods, and with function (Western Ontario Shoulder Instability, Quick-Disabilities of the Arm, Shoulder and Hand). Results: Thirty-two patients met the inclusion criteria: three females and 29 males, mean age 28 years. The intra- and inter-observer reliability was excellent, with intraclass correlation coefficient ranging from 0.817 to 0.938 for the novel Clock method. Humeral Clock and Glenoid Clock strongly correlated with Humeral Ratio ( r = 0.882, p < 0.001) and Glenoid Surface Area and Glenoid Ratio ( r = 0.793 and 0.717, p < 0.001), respectively. The classic threshold of 25% of the glenoid diameter with the Glenoid Ratio method corresponds to 4 hours with the Glenoid Clock method. Conclusions: The Clock method is quick and reliable, with more studies being needed to investigate whether it is correlated with surgical outcomes.